Awesome Linux command line

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To be honest with you, I like command line so much, even before I became familiar with Linux, I used to use DOS command prompt extensively, which in comparison with Linux command line is nothing.

After, I had experienced Linux for the first time, I have fascinated how it is powerful and how many tasks can be automated without writing a single line of code or bash script or doing it manually. For instance, many times I wanted to extract certain columns of a big text file without opening it and many other things.

This time I wanted to retrieve certain portion of text from a huge log file which contains some words and not extract the entire line but extract the content which has that particular word and the rest of the sentence.

For instance, I had the following sentence,

Hello world 1234, testing

My objective is to extract world 1234, testing by checking for the word world. In order to do so, I have used the following command line,

$ less Mylog.txt | grep -o 'world.*'

Now the next step is to remove the word world from the output in order to become only, 1234, testing. For doing that I changed the command like below,

$ less Mylog.txt | grep -o 'world.*' | cut -f2- -d':'

But the work has not done yet, I want to replace comma by new line to ensure each line has only one word. Therefore, the command extended like this,

$ less Mylog.txt | grep -o 'world.*' | cut -f2- -d':' | tr -s ',' '\n'

Now, the last step is to sort the content of the file and extract only the unique lines because some lines might be duplicated. And the last result become like this,

$ less Mylog.txt | grep -o 'world.*' | cut -f2- -d':' | tr -s ',' '\n' | sort | uniq

You see how it is possible to do complicated things with Linux command line and save huge amount of time.